River connectivity and fish migration considerations in the management of multiple stressors in South Africa

2019 ◽  
Vol 70 (9) ◽  
pp. 1254 ◽  
Author(s):  
Gordon C. O'Brien ◽  
Mathew Ross ◽  
Céline Hanzen ◽  
Vuyisile Dlamini ◽  
Robin Petersen ◽  
...  
Keyword(s):  
South Africa ◽  
Multiple Stressors ◽  
Fish Passage ◽  
Freshwater Ecosystems ◽  
Management Approach ◽  
Freshwater Ecosystem ◽  
Fish Migration ◽  
Human Land Use ◽  
Provision Of Services ◽  
Connectivity Maintenance

People throughout the world depend on the services we derive from freshwater ecosystems. Human land-use activities often affect the quality, quantity and habitat of freshwater ecosystem, which need to be carefully managed to ensure their integrity and provision of services is sustainable. In South Africa, legislation has established resource-directed measures to attain a sustainable balance between the use and protection of water resources. These procedures have been implemented in most of South Africa’s nine water-management areas, resulting in new legislation to protect these resources. Unfortunately, very little protection has been afforded to river connectivity maintenance and fish migrations. For water storage and flow regulation for agriculture and other resource use activities, >610 formal dams and ~1430 gauging weirs have been constructed that act a partial or complete barriers to fish migration on river ecosystems. Only ~60 fish passage structures have been built, but many are not functional. River connectivity and fish migration management appears to be a shortcoming of the existing management approach for multiple stressors.

scholarly journals Turning Pools in Stepped Fishways: Biological Assessment via Fish Response and CFD Models

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1186
Author(s):  
Francisco Javier Bravo-Córdoba ◽  
Juan Francisco Fuentes-Pérez ◽  
Jorge Valbuena-Castro ◽  
Andrés Martínez de Azagra-Paredes ◽  
Francisco Javier Sanz-Ronda
Keyword(s):  
3D Models ◽  
Fish Passage ◽  
Biological Assessment ◽  
Fish Migration ◽  
Longitudinal Development ◽  
Passive Integrated Transponder ◽  
Design Component ◽  
Cfd Models ◽  
Vertical Slot ◽  
Fish Response

With the aim of building more compact fishways and adapting them to field conditions to improve their location by fish, it is common to use turning pools, reducing the longitudinal development of the construction. However, depending on their design, turning pools may affect the hydraulic performance of the fishway and consequently the fish passage. To study these phenomena, turning pools in a vertical slot and in different configurations of submerged notches with bottom orifice fishway types were assessed. Both types of fishways were studied using numerical 3D models via OpenFOAM, a computational fluid dynamics software, in combination with fish responses, assessed with PIT (Passive Integrated Transponder) tag telemetry for three different species of potamodromous cyprinids in several fishways. Results show differences between the hydrodynamics of straight and turning pools, with lower values in the hydrodynamic variables in turning pools. Regarding fish behavior, the ascent was slower in turning pools but with no effect on passage success and without being a problem for fish migration. This information validates the use of turning pools as a key design component for fishways for studied species.

The Future of Water

2019 ◽  
pp. 227-232
Author(s):  
Edward B. Barbier
Keyword(s):  
Water Security ◽  
Freshwater Ecosystems ◽  
Freshwater Ecosystem ◽  
World Population ◽  
Policy Reforms ◽  
Global Management ◽  
Market Signals ◽  
The World ◽  
The Future ◽  
The One

This concluding chapter looks at the future of water. There are two possible paths for managing water. First, if the world continues with inadequate governance and institutions, incorrect market signals, and insufficient innovations to improve efficiency and manage competing demands, most chronic water and scarcity problems will continue to worsen. The world will see a future of declining water security, freshwater ecosystem degradation, and increasing disputes and conflicts over remaining water resources. The alternative path to managing water is the one offered by this book. If, in anticipation of the coming decades of increasing water scarcity, humankind is able to develop appropriate governance and institutions for water management, instigate market and policy reforms, and address global management issues, then improved innovation and investments in new water technologies and better protection of freshwater ecosystems should secure sufficient beneficial water use for a growing world population.

scholarly journals 'Hidden messages' emerging from Afrocentric management perspectives

2008 ◽  
Vol 8 (1) ◽  
Author(s):  
H. Van den Heuvel
Keyword(s):  
South Africa ◽  
Cultural Diversity ◽  
South African ◽  
The Body ◽  
Management Approach ◽  
Local Management ◽  
Valuable Contribution ◽  
Corporate Values ◽  
Management Discourse ◽  
Research Findings

Purpose: This paper aims to examine how 'African management' discourse has emerged in South Africa. Altogether, it has stimulated debates - sometimes in controversial ways - on 'taboo issues', e.g. relating to 'cultural diversity' and 'ethnicity'. The stimulation of such debates within organisations is probably a more valuable contribution than a static, essentialised 'African identity' that it proclaims. Design/Methodology/Approach: The paper draws on a qualitative research project conducted in South Africa in 2003-2004. Its relevance lies in gaining in-depth insights into ('non-western') local management discourse. It seeks to contribute to the body of knowledge on political and cultural contexts in which South African organizations operate, and how they impact on local management perspectives, and vice versa. Findings: The research findings make clear how and under what circumstances 'African management' discourse has come about in South Africa, and how it could be interpreted. Implications: 'African management' advocates allegedly attempt to revise dominant management thinking and promote 'humane-ness' and participatory decision-making in South African organisations, in search of a contextualised management approach. Amongst others, it has produced new meanings of 'Africanness' and has opened up space for 'hidden messages', resentments and aspirations to become openly articulated. This throws another light on phenomena such as cultural diversity and ethnicity that usually tend to be 'neutralised'. This may turn out to be far healthier for blooming organisational cultures in South Africa than relentlessly hammering on prescribed 'corporate values'. Originality/Value: This paper informs the reader in detail about the emergence and evolvement of 'African management' discourse in South Africa. It is a unique attempt to develop an interpretative viewpoint on this intriguing phenomenon that offers a potentially valuable contribution in reading cultural and ethnic identities within organisations.

Water Quantity and Hydrology

2018 ◽  
pp. 67-88 ◽  
Author(s):  
Matthew McCartney
Keyword(s):  
Water Discharge ◽  
Freshwater Ecosystems ◽  
Freshwater Ecosystem ◽  
Ecosystem Structure ◽  
Freshwater Biodiversity ◽  
Freshwater Habitats ◽  
And Function ◽  
Induced Changes ◽  
Ecosystem Structure And Function ◽  
Hydrological Monitoring

Freshwater ecosystems are naturally dynamic. The source of water, discharge, turnover, and residence times all affect which organisms can live in different freshwater habitats and are key determinants of freshwater ecosystem structure and function. Human-induced changes to the volume and timing of both surface and ground water flows are a leading driver of global declines in freshwater biodiversity and are likely to be exacerbated by climate change. The conservation of many wetlands around the world, including in some cases the preservation of unique flora and fauna, is now entirely dependent on continued human intervention and water management. Such management can only be successful if based on sound understanding of water budgets and hydrological processes informed by accurate hydrological monitoring. This chapter provides a brief introduction to hydrological monitoring—what needs to be measured and how—for freshwater ecology and conservation.

Public sector entrepreneurship in South Africa

2019 ◽  
Vol 8 (4) ◽  
pp. 500-512
Author(s):  
Boris Urban ◽  
Mmapoulo Lindah Nkhumishe
Keyword(s):  
South Africa ◽  
Public Sector ◽  
South African ◽  
Middle Level ◽  
Primary Data ◽  
Content Type ◽  
The Public ◽  
Provision Of Services ◽  
Efficiency And Effectiveness ◽  
Organisational Factors

Purpose Many unanswered questions remain regarding the authors’ understanding of how entrepreneurship can be fostered in the public sector. To fill this knowledge gap, the purpose of this paper is to conduct an empirical investigation to determine the relationship between different organisational factors and entrepreneurial orientation (EO) in the South African public sector. Design/methodology/approach Primary data are sourced from middle-level managers at municipalities in the three largest provinces across South Africa. Hypotheses are statistically tested using regression analyses. Findings Results reveal that the organisational antecedents of structure and culture explain a significant amount of variation in the EO dimensions of innovativeness, risk taking and proactiveness. Additionally, the findings on organisational rewards converge with an emerging stream of research which highlights that while rewards works well to motivate individuals in the private sector, they are negatively correlated with entrepreneurship in the public sector. Research limitations/implications The study implications relate to the efficiency and effectiveness of service delivery of municipalities in South Africa. Due to increases in community protest actions, it is necessary not only to maximise efficiency in the provision of services, but also to innovate and be proactive in order to achieve more with less resources. Originality/value By investigating previously unrelated factors in the public sector, the authors create closer conceptual and empirical links between the role of organisational factors and each of the EO dimensions. Furthermore, the study takes place in a relatively under-researched entrepreneurship and public sector context.

scholarly journals Scavenging by threatened turtles regulates freshwater ecosystem health during fish kills

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Claudia Santori ◽  
Ricky-John Spencer ◽  
Michael B. Thompson ◽  
Camilla M. Whittington ◽  
Thomas H. Burd ◽  
...  
Keyword(s):  
Water Quality ◽  
Ecosystem Health ◽  
Freshwater Ecosystems ◽  
Freshwater Ecosystem ◽  
Freshwater Species ◽  
Freshwater Turtles ◽  
Fish Kills ◽  
Murray Darling Basin ◽  
Ecological Implications ◽  
Mesocosm Experiments

Abstract Humans are increasing the frequency of fish kills by degrading freshwater ecosystems. Simultaneously, scavengers like freshwater turtles are declining globally, including in the Australian Murray–Darling Basin. Reduced scavenging may cause water quality problems impacting both ecosystems and humans. We used field and mesocosm experiments to test whether scavenging by turtles regulates water quality during simulated fish kills. In the field, we found that turtles were important scavengers of fish carrion. In mesocosms, turtles rapidly consumed carrion, and water quality in mesocosms with turtles returned to pre-fish kill levels faster than in turtle-free controls. Our experiments have important ecological implications, as they suggest that turtles are critical scavengers that regulate water quality in freshwater ecosystems. Recovery of turtle populations may be necessary to avoid the worsening of ecosystem health, particularly after fish kills, which would have devastating consequences for many freshwater species.

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